Single SELECT vs. multiple SELECTs on UNrelated tables ??

SELECT * FROM TABLE_A a, TABLE_B b where a.col1=1 and b.col1=99 [this returns 1,2,3,98,99]

versus

SELECT * FROM TABLE_A a where a.col1=1 [this returns 1,2,3]

SELECT * FROM TABLEB b where b.col1=99 [this returns 98,99]

These are two absolutely unrelated tables and each return only one row for the above specified conditions. So my question is:

which is more efficient: the one select or two selects?

To add more complexity, if this is a client/server application and you want as few "across-the-network" calls to the database as possible, would the single select have even greater merit. I would think so, but am interested in input from the SQL world.

Thanks.

Chris Received on Thu Oct 03 1996 - 00:00:00 CEST